Regensburg 2025 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 39: Poster III
HL 39.4: Poster
Mittwoch, 19. März 2025, 15:00–18:00, P3
Temperature Dependence of the Quantum Efficiency of UV LEDs emitting from 226 nm to 300 nm — •Max Eysell1, Jakob Höpfner1, Marcel Schilling1, Norman Susilo1, Anton Muhin1, Massimo Grigoletto1,2, Tim Kolbe2, Arne Knauer2, Sylvia Hagedorn2, Markus Weyers2, Jens Rass2, Hyun Kyong Cho2, Tim Wernicke1, Sven Einfeldt2, and Michael Kneissl1,2 — 1Technische Universität Berlin, Institute of Solid State Physics, Berlin, Germany — 2Ferdinand-Braun-Institut (FBH), Berlin, Germany
UV-LEDs are of huge interest for e.g. air, surface, and water disinfection. However, the widespread application of UV-LEDs is constrained by their external quantum efficiency (EQE) which is decreasing further as the emission wavelength shortens. To gain insight into the carrier transport and recombination mechanisms, a detailed analysis of the EQE of UV-LEDs and the three contributors: the carrier injection, the radiative recombination and the light extraction was performed.
The emission power of LEDs with emission wavelengths of 226 nm, 233 nm, 265 nm and 305 nm are investigated by temperature dependent electroluminescence measurements in the range of 25−80 ∘ C. A reduction in emission power and EQE has been observed going from UVB to the far-UVC spectral range. A thermal droop in the emission power was observed for all samples which is caused by the decline of all three contributions. The magnitude of this thermal droop becomes higher with decreasing wavelength which we attribute to an increased electron leakage suggested by Schrödinger-Poisson drift-diffusion simulations.
Keywords: UV-LEDs; AlGaN; electroluminescence